jorisbots3
Hi
Let me share answer one by one.
Does Jomsocial have the option to add custom fields to the user registration (such as Company, linkedin url, function etc)?
Yes,JomSocial provide registration custom fields to add new fields. You can go to Jomsocial configuration > Profile and add new fields.
Does it have the option to add categorie(s) to posts and view posts in one category?
All text type post does not use any categories, all post will show on stream items.
Does it have polls for voting / rating on for a list of items (so they can collaborate in which item on that list is found best)
Yes, JomSocial has Poll feature that allow user to vote for given options.
Does Jomsocial have the feature of quick login / registration with linkedin? (nice to have, not need to have)
JomSocial does not have not this option, there are 3rd party extension that works for this, we have this feature in list but it will take sometime to added in core.
- Does it have Acymailing integration?
JomSocial is independent extension for social community, you need to check this with Acymail if they provide any type integration.
I suggest you to take a look on the demo to see all the features here
Regards